A need presently exists for a T-tap type connector which can be waterproof if desired, which has an opening between the terminals of the connector so that a continuity test can be carried out after the connector has been installed on the through wires and the tap wires, and which additionally is such that the tap wires or the through wires can be connected to the terminals prior to connecting the remaining pair of wires to the terminal. For example, there are occasions when it is desirable to connect tap wires, which may extend to an instrument or to an electrical device, on one occasion and at a later time connect the tap wires to the through wires. While there are a wide variety of tap-type connectors available, there are none which would satisfy the requirements as discussed above. The present invention is directed to the achievement of such a connector.